| January 17 | Captain Cooks last notation in ship's log Discovery |
| January 23 | Charles Messier catalogs M56 (globular cluster in Lyra) |
| January 31 | Charles Messier adds M57 (Ring Nebula in Lyra) to his catalog |
| February 24 | George Rogers Clark captures Vincennes (Ind) from British |
| March 11 | U.S. Army Corps of Engineers established (1st time) |
| May 13 | War of Bavarian Succession ends |
| June 15 | General Anthony Wayne captures Stony Point, Bronx |
| June 16 | In support of the U.S., Spain declares war on England |
| June 16 | Vice-Admiral Hardy sails out of Isle of Wright against Spanish Armada |
| June 18 | French fleet occupies St. Vincent |
| June 20 | Battle of Stone Ferry |
| July 4 | French fleet occupies Grenada |
| July 15 | U.S. troops under General A Wayne conquer Ft. Stony Point, New York |
| September 3 | Earl d'orvilliers (French/Spanish Armada) sails back to Brest |
| September 23 | John Paul Jones' "Bon Homme Richard" defeats HMS Serepis |
| September 27 | John Adams negotiates Revolutionary War peace terms with Britain |
| December 23 | Benedict Arnold court-martialed for improper conduct |
| December 31 | English fleet beat Dutch Merchant vessels |
